T：teacher S：student

T: We'll review some knowledge we learned last class.I ask and you answer.Just sit in your seat and answer if you know the answer without hand up.Now let's begin.

T:The longest river in the world?

S:The Nile in north Africa.

T:The highest mountain in the world?

S: Qomolangma in the Himalaya Mountains.

T:The biggest lake?

S: Caspian Sea between Asia and Europe.

T:Great!You all know the most lake,mountain and so on,but who can tell me the second ones? I want to tell you that when you choose to do one thing,there is no best but only better and better.